Abstract: A dynamically selectable multimode pulse width modulation system includes ramp generator means for generating a ramp; pulse edge modulation means responsive to the ramp generator means for defining a leading edge modulated pulse, a trailing edge modulated pulse and a dual edge modulated pulse; and mode selection means responsive to the pulse edge modulation means for selecting one of the leading edge modulation, trailing edge modulation, and dual edge modulation modes of pulse width modulation.
Abstract: A horizontal cable animal barrier for mounting on a cable to deter animal passage including a plurality of roller elements each having a central hole for rotatably mounting on a cable and a spacer element between each pair of roller elements and also having a central hole for rotatably mounting on the cable, in which the spacer elements are of a different size than the roller elements on either side to present an uneven, rotating barrier to animals on the cable to prevent the animals from passing.
Type:
Grant
Filed:
April 5, 1991
Date of Patent:
March 15, 1994
Assignee:
The Omt Group
Inventors:
James T. Richard, George J. Costigan, David J. Perry, Kevin T. Eldridge
Abstract: An apparatus and method for facilitating the positioning of a live image with respect to a reference image in which the live and reference images are combined to produce a composite image that is displayed.
Abstract: A flexure for an accelerometer includes an inner hub; an outer rim spaced from the inner hub; one of the hub and rim being mounted to the accelerometer body and the other to the proof mass of the accelerometer; at least three curved tapered beams extending between the rim and the hub with the widest beam portion proximate the rim, for flexibly supporting the proof mass and enabling relative rotational relief between the hub and rim for preventing nonlinear stretching of the beams.
Type:
Grant
Filed:
August 26, 1992
Date of Patent:
March 8, 1994
Assignee:
The Charles Stark Draper Laboratory, Inc.
Inventors:
John M. Barry, Anthony Petrovich, Thomas E. Shelvey
Abstract: A system and method for damping narrow band axial vibrations of a rotating device in which a reaction mass is coupled to the rotating device and a reaction mass actuator is employed to move the reaction mass axially along the rotating device. An effect of vibrations on the rotating device is then measured, and in response the reaction mass is moved axially to damp the effect of vibrations and so the vibrations.
Type:
Grant
Filed:
October 27, 1992
Date of Patent:
March 8, 1994
Assignee:
SatCon Technology Corporation
Inventors:
Bruce G. Johnson, Richard Hockney, David Eisenhaure, Ralph Fenn
Abstract: A multiplexed single channel knock sensor signal conditioner system for internal combustion engines includes a plurality of sensors for sensing the vibrations associated with knocking in an internal combustion engine; a single signal conditioning channel for providing a signal level representative of the magnitude of the knock; and means for selectively connecting the sensors to the signal conditioning channel. The signal conditioning channel includes a band pass filter, the frequency characteristics of which are adjusted according to the sensor connected to the signal conditioning channel.
Abstract: A process for depositing on a sample surface a smooth, wear-resistant coating including the steps of providing a vacuum processing chamber for holding the sample to be coated, introducing into the processing chamber coating-forming reactants for deposition on the sample surface, and supplying to the processing chamber a plasma stream with an electron temperature of up to 10 eV, a directed ion energy of 5 to 50 eV, and an ion flux at the sample in the range of 0.1 to 100 milliamps per square centimeter for transferring energy to the deposited material to form the smooth coating.
Abstract: A linearized ferroelectric capacitor includes a ferroelectric dielectric medium; a doped region in the ferroelectric dielectric medium, the doped region having a charge of a first polarity which divides the medium into two sections of opposing polarized domains; and a pair of electrodes on the ferroelectric medium having a contact potential of a second, opposite polarity to that of the doped region for reinforcing and stabilizing the polarized domains in each section.
Abstract: A cask for storing and transporting highly radioactive materials includes an inner shell and a number of layers of depleted uranium wire wound on the inner shell to create a radioactive shield against emanation of radioactivity from the material stored within the inner shell.
Abstract: An ultra-fast quenching device for rapidly quenching material includes a housing for defining a quenching area. A plurality of inlet ports are disposed in the housing and are generally evenly distributed within the housing for controlling the locations and amounts of quenching fluid discharged against a surface of material disposed in the quenching area. A plurality of exhaust ports are disposed interstitially among the inlet ports for removing quenching fluid local to the inlet ports to control the rate and profile of heat transfer, from the material to the quenching fluid, across the surface of the material.
Type:
Grant
Filed:
January 30, 1989
Date of Patent:
March 10, 1992
Assignee:
The Charles Stark Draper Laboratory, Inc.
Inventors:
Jacob H. Martin, Frederick D. Browne, II
Abstract: A method of removing niobium from a uranium-niobium alloy includes dissolving the uranium-niobium alloy metal pieces in a first aqueous solution containing an acid selected from a group consisting of HCl and H.sub.2 SO.sub.4 and a fluoboric acid as a catalyst to provide a second aqueous solution which includes uranium (U.sup.+4), acid radical ions, the acids and insolubles including uranium oxides and niobium oxides; adding nitric acid to the insolubles to complete the oxidation of the niobium oxides to yield niobic acid and further solubilizing thr uranium oxide; and separating the niobic acid, nitric acid and solubilized uranium oxides.
Type:
Grant
Filed:
November 13, 1989
Date of Patent:
January 28, 1992
Assignee:
Nuclear Metals, Inc.
Inventors:
Eugene N. Pollock, David S. Schlier, George Shinopulos
Abstract: A signal digitization system and method is disclosed which identifies a plurality of sets of spaced intervals of information; defines a strobing window within each spaced interval in one of the sets at a time; strobes the signal during the strobing window; integrates and holds the strobed signal; and digitizes the integrated signal.
Type:
Grant
Filed:
July 24, 1990
Date of Patent:
July 23, 1991
Assignee:
Analogic Corporation
Inventors:
Enrico Dolazza, Alexander Kolchinsky, Richard McMorrow, Jeremy Muller, Hans Weedon
Abstract: A method of obtaining effective faying in joining parts includes forming a first and second member into predetermined complementing shapes. The members are then placed together and sealed along a peripheral track to form a chamber between the members. The method further includes applying a pressure differential to the members with the lesser pressure residing in the chamber and heating the members to soften at least one of the members to conform the members to each other under the force of the differential pressure.
Type:
Grant
Filed:
December 5, 1990
Date of Patent:
July 16, 1991
Assignee:
The Charles Stark Draper Laboratory, Inc.
Abstract: A circumferentially stirred variable residence time vortex combustor including a primary combustion chamber for containing an annular combustion vortex and a first plurality of louvres peripherally disposed about the primary combuston chamber and longitudinally distributed along its primary axis, the louvres inclined to impel air circumferentially about the primary axis within the primary combustion chamber, to cool its interior surfaces, to impel air inwardly to assist in driving the annular combustion vortex in a helical path, and to feed combustion in the primary combustion chamber. The vortex combustor further includes a second annular combustion chamber and a narrow annular waist region interconnecting the output of the primary combustion chamber with the second annular combustion chamber for passing only lower density particles and trapping higher density particles for substantial combustion in the annular combustion vortex of the primary annular combustion chamber.
Abstract: An aneroid volume determining system includes an airtight chamber for holding a subject whose volume is to be detected; a volume adjuster including an inflatable container for varying the pressure in the chamber; sensing equipment including a pressure transducer for sensing the pressure in the chamber in the deflated and inflated states of the container; and controlling equipment, which can calculate the volume of the subject in response to the pressure sensed in the chamber with and without the subject present in the chamber and which equipment provides control signals to the volume adjuster for automatically controlling the inflation and deflation of the inflatable container.
Abstract: A mode-selectable communications system which commands one or more remote modules from a controller unit. The controller unit issues a command signal having an address and major communications mode command. Each remote module includes a major mode identifier for receiving the command signal from the control unit through a communications link. The major mode identifier identifies an address pertaining to the module and identifies a major communications mode for that module as a command response mode or a time slot mode. The module implements a task indicated by the command mode and selects a time slot response based on the time slot mode. A time slot unique to that module is determined and the module communicates with the control unit through the communications link during that time slot.
Abstract: A movable calibration collimator for a radionuclide emission tomography camera, and a calibration system using same, having a wall of material which is opaque to radionuclide emissions and is movable in a first direction relative to the camera. One or more patterns of openings are defined by the wall to pass radionuclide emissions. The openings of each pattern are aligned in a direction transverse to the first direction to provide an array of camera images upon movement of the wall relative to the camera. The number of images generated for the array are greater than the number of openings. A method of using such a calibration collimator to perform linearity correction involves installing the calibration collimator and a line source of radionuclide emissions, acquiring a camera image of the pattern of openings, and incrementing the calibration collimator for a desired number of increments. Each camera image, collected at each position of the collimator, has a position image for each opening.
Abstract: A switching system for controlling rf energy through an rf transmission medium including a plurality of semiconductor switching devices connected in a series configuration with the primary electrodes connected in series, and means for providing graduated bias on the control electrodes for establishing an equal control voltage on each device between its control electrode and one of its primary electrodes.
Abstract: A container for a paint brush, which container comprises a body and a lid, the body having a base and a walled portion which upstands from the base, the lid having an aperture through which a handle of the paint brush passes and slits which extend from the aperture and which enables parts of the lid defining the aperture to grip the handle of the paint brush, and the walled portion of the body having an inwardly projecting integrally formed shelf portion on which to rest the paint brush, and integrally formed ribs which extend parallel to the base and which are for wiping excess paint from the paint brush.
Abstract: A self-balancing circuit for convection air ionizers with a passively balanced ion emitter and collector including a circuit in which the ion emitter and the collector are capacitively isolated from external charge sources or sinks for maintaining balance in the positive and negative charge for producing a zero average current flow and a charge balanced ionized airstream.
Type:
Grant
Filed:
February 16, 1989
Date of Patent:
April 16, 1991
Assignee:
Chapman Corporation
Inventors:
Ralph W. Swanson, Daniel F. Gagnon, Donald G. Parent